EP 0066151 A2 19821208 - Hydraulic control system comprising a pilot operated check valve.
Title (en)
Hydraulic control system comprising a pilot operated check valve.
Title (de)
Hydrauliches Steuersystem mit vorgesteuertem Rückschlagventil.
Title (fr)
Système hydraulique de commande avec clapet anti-retour piloté.
Publication
Application
Priority
US 26785381 A 19810528
Abstract (en)
A hydraulic control system comprising a hydraulic actuator having opposed openings adapted to alternately function as inlet and outlets for moving the element of the actuator in opposite directions, a pump for supplying fluid to the actuator, pilot operated meter-in valve means to which the fluid from the pump is supplied for controlling the direction of movement of the actuator, meter-out valve means associated with each opening of the actuator for controlling the flow out of said actuator, and a pilot operated check valve (100) operable for controlling flow from the meter-in valve means to one end of the actuator and for preventing flow out the end of said actuator, the pilot operated check valve (100) being operable at a lower pilot pressure than the meter-out valve means and including time delay means (112, 115a, 119) such that the valve (100) functions to prevent flow out of the actuator after a predetermined time delay from the time when pilot pressure to said meter-out valve means is interrupted, ensuring relief valve protection.
IPC 1-7
IPC 8 full level
F15B 11/08 (2006.01); F15B 13/01 (2006.01)
CPC (source: EP US)
F15B 13/015 (2013.01 - EP US)
Designated contracting state (EPC)
DE FR GB IT SE
DOCDB simple family (publication)
EP 0066151 A2 19821208; EP 0066151 A3 19831012; EP 0066151 B1 19860212; AU 552064 B2 19860522; AU 8323182 A 19821202; BR 8203096 A 19830607; CA 1168957 A 19840612; DE 3269048 D1 19860327; IN 155800 B 19850309; JP H0229881 B2 19900703; JP S57200704 A 19821209; MX 155455 A 19880311; NZ 200516 A 19850320; US 4418612 A 19831206
DOCDB simple family (application)
EP 82104214 A 19820514; AU 8323182 A 19820503; BR 8203096 A 19820527; CA 400186 A 19820331; DE 3269048 T 19820514; IN 540CA1982 A 19820514; JP 7981782 A 19820512; MX 19242382 A 19820426; NZ 20051682 A 19820504; US 26785381 A 19810528